Apparatus for automatically stopping die casting machines in the event of shot failure



L. H. MORIN APPARATUS FOR AUTOMATICALLY STOPPING DIE CASTING MACHINES INTHE EVENT OF SHOT FAILURE Oct. 20, 1953 Filed July 19, 1951 PatentedOct. 20, 1953 P-ING nm- CASTING IN THE? EVENT- :oF: snow: FAILURE'L:

IIcuis HaMorin, Bi-onx., N..Y

ADDITcafiOnJuIy IS; 1951, Serial No. 237,611

(Gil an-'10) 7 5:01am. 1 t

This invention .irelatesito die-casting;machines More particularly;theqinvention dealswith an apparatus for automatically, stopping; theoperation: f theam-achine the event that the-"shot stroke of thegooseneck; of; the machinesshould fail to fimctiongfor anyz-ireason;sotas to render theumachine inoperative until v such time as the faultis:- corrected. Still more particularly; the invention deals: withaa;mechanism of the characteradescribed; which is Ldirectly. tied in with.the automatically; actuated valve controlling supply. of compressed-airto-ethe plunger: controlling discharge of molten metalefrom thegoosen'eckb Theinovelvfeatures ofjtheinvention will be best understoodifrom. the fojll'owing description, when takemtogether withzstheaccompanyingrdrawing, in which certain embodiments :of the inventionareodisclosed' and;in" which,..the: separate partsare'rdesignated*byrsuitable reference characters.

The drawing: iss'a diagrammatic vsectional view through thegooseneckiandoperating mechanism therefor; showing the valve which controls theoperation. of-asaid mechanism andillustrating my improved'automatic'stop;

In digac-asting m'a'chines-- and particularly, machines of I this classwhichz operate automatically at high speeds; it is customary to provideone attendant. to a large number of I machines. At times, :it has: beeni experienced that a --nozzl'e-' or other cloggingstakes place; whichclogging-might compriseaa freezing of-metal at the d-ischarge of thenozzle; Omthe other hand, a -gate :may clog the nozzle holei-controllin'g-- admission to a die cavity:

Imautom'aticmachines"of the kindunder considerationyl the development ofI such a clogging con'dition woul'dresult in -the machine continuing tooperateIor a period of time; until this fault weuld be noted by anoperator andithisimproper functionin'g'of the machine, if nothingelsei'would' result a production} loss "and the" failure to produ'eedi'ecastings-in;eaelrcycleof operation of the machine:

The -objector my present invention-deals withi the provision ofan-automatic-'- stop -mechan-ism which willinstantaneously stop theoperation -of the: m-achine av the-moment-that*thedischarge lunger, for(iischargingmolten-imetalfiomWhe nozzl'e oflthe-machine, fails-topertorm itsnormal' function: and 'this automatic stop mechanism is tiedin} .withinth'e lair control-' valve in -a simple manner; sozastoxutil-izeithesame airfon actuation ofya stop :switch whichwilla-brealcthe motor: cir= l 1t": causing;thegmachme to;stop-immediately; particularly-., in; utilizing it braketype.- of='motor for actuatingthe casting machine.

Invthefiaccompanyingj drawing; I have diagrams matically shown suchparts of a -die castingtmaachine; as will: illustrate the function andopera-- tion of-my improved-automatic stop, mechanism In the: drawing,1| 0 represents a conventional pot con-taining' the molten metal H, thepot :haw ing suitable means'for heating th'e' same; aSflin-E-dicated-atrl2; toxmaintain thermetal ilyat the proper temperaturesSupported; in and above the pct:'is-a-gooseneckrmechanism- 35 comeprisingalower discharge'cylinder 14-}: n:-wliich the discharge plungerI5vopera'tes;v -.the: cy1inder. 14 having the upwardly and outwardlyextending discharge arm 16- having; at itsendpthe conventional dischargenozzleil,-.- through which: the heatedmetal is adapted to bepressuredischarged into the cavity of:suitable diea-zwthe. latter-beingomitted.

Above the cylinderv ,1 4 is a 1 cylinder I 8-; which joins -thercylinderl4, ina SBIiBS-OfllbSglQa The plunger; extendsv :into the cylinder :lhandshas thereon a piston '20 with an, O-ringror. other-seal 2 I --inthecylinder I 8.

Thelower; endof-thecylinder l8 has aiseat 22 for a;-coilw-spring-i 23which bears against, the piss ton- 2thto; normallysupport the same and.the

plunger IS in raised position. Air is exhausted from-atheicylinder I8through-t clearance}, at 24;: between theseat 2l'zandplunger. I5;Theplunger; l5 includesan extension;2-5gcaboverthe' pistonand operatingin a suitable: bearing block 2 6.; the" extension 1 25-;extendingmaboveathe block and having an adjustable collar-I-l-thereon; the-collar havinga-radialarm= 28min whichiis supported an adjustable screw 29. I

The screw 2 9 operates upon iaispring gbackedrpin 30;operating inwa bypass control tapered VaIVB'iI-I which controls by-passingof-compressed-air. from port-=3 2- to pipe ,3 3 extending rtones-suitably; sup-1- ported-small cylinder 34;: in which via-mounted apiston actuated-pin 352- Thewpin Must-normally.-

set by a spring 36 and, when -actuated :1by:air

againstythe :action of 'the. spring ;:saidz-pinwill operate ai-buttonp31 of a: microaswiteh r38: The. switch controlsthe circuit to theelectric motor 39; which isof a brake-type and=Jisdiagrammati v callyshown v in the accompanying-drawing:' The motor- 39 controls the.operation of thecasting machine; Thus; it will be apparent-that; whenthew m-icro-switch (i8: is actuated; the machine will (beinstantaneously stopped:

Atoneside of thecylinder H3 isa .tubularvalve casing, 40, in which .isslidably mounted -acontrolvalved I The-valve l l carries; at itsouter-forkedend A 2;: .a roller- 43 held ,in constant engagement with anoperating cam 44 bya coil spring 45. It

3 will be understood that the shaft 46 of the cam is automaticallyactuated from the motor 39 through a suitable drive, which is not shown.

As will appear, the roller 43 operates in an open end portion 41 of thecasing 40 and, in the position shown, the valve 4| has been actuated bythe cam 44, so as to place the port 48 of the valve in communicationwith the source of compressed air supply as through pipe 49 with thepipe 50 which leads to the admission port of the cylinder I8 and,accordingly, the piston will, in such position, be moved downwardly toactuate the discharge plunger. In the drawing, it is shown in the raisedposition. It will be understood, however, that, as air enters thecylinder IS, the piston 20 will be moved downwardly for actuation of theplunger I5.

The pipe contains a T-coupling 52 that has a branch 53 connected to thevalve casing 4|]. When the rise or bump 54 on the cam 44 moves the valve4| further into the casing 40, a port 55 in the valve is positioned soas to place the branch 53 in communication with pipe 58. Air will thusbe admitted to the port 32 in a direction to raise or open the by-passvalve 3|. However, under normal conditions; i. e., when the piston 20and plunger I5 have moved downwardly for their full stroke, the screw 29carried by the extension 21 of the plunger engages with the pin 39 andholds the valve 3| seated or closed, thus preventing air from enteringthe pipe 33 from the port 32 and, consequently, the micro-switch 38 willnot be operated.

The foregoing statement is on the normal successful operation of theplunger i5 in pressure discharging metal from the goosenecir M or nozzleI into a die cavity. However, should the plunger l5 be checked or heldagainst it full downward movement by a clogged condition prevailinganywhere in the line of flow of metal to the die cavity, then thechecked downward movement of the plunger l5 will prevent the valve 3|from being held in its seated or closed position and air will bepermitted to pass into the pipe 33 from the port 32 to actuate the pin35, button 31 and microswitch 38, thus instantaneously stopping themotor 39.

The inner end of the valve 4| has an exhaust passage 51 which is adaptedto register with the pipe 55 when the cam 44 is in its low position, so

as to exhaust air from the pipes 33, 56 through the exhaust port 58 inthe casing 40. The casing 40 has another exhaust port 59, at its outerend, with which the port 48 communicates for exhausting air from thecylinder I8 and pipe 50 in the same position of the valve 4|, mentionedabove. For this purpose, the end of the port 48 communi eating with thepipe 50 is elongated so that it remains in communication with the pipe50 in the latter position of the valve 4|, but the supply of compressedair from the pipe 49 is shut-off by the movement of the valve 4| Byproviding the adjustable screw 29 for actuating the pin 39, a definitesetting can be made to control the seating of the valve 3| in theoperation of the machine. From the foregoing, it will be apparent that,in each cycle of operation of the cam, the valve 4| will complete itsinward and outward stroke motion and, in normal operations of themachine and when a casting charge or shot has been successfullydischarged from the nozzle ll, the machine will continue to function,the valve 3| being, at all times, held in its seated position when airis admitted thereto. However, if a full charge or shot of castingmaterial has not taken place, the valve 3| will be free to be opened andthe micro-switch will be actuated instantaneously to stop operation ofthe machine. At least, this operation will be performed before anothercycle of operation of the machine takes place.

Having fully described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a die casting machine of the character described which employs agooseneck and a plunger operating in the gooseneck for dischargingmolten metal under pressure into a die cavity, the combination ofpneumatically operable means for controlling the operation of themachine, a. valve connected to a supply of air under pressure, saidvalve in one position connecting the supply of air to the plunger in thegooseneck and in second position connecting the supply of air to saidpneumatically operable means, asecond valve connecting the pneumaticallyoperable means to the supply of air through said first-mentioned valveand means controlled by movement of the plunger for holding saidsecond-mentioned valve closed at one position of the plunger.

2. In a device for automatically controlling the operation of a diecasting machine of the type employing a gooseneck with a plungeroperating therein for discharging molten metal under pressure into a diecavity, the combination of pneumatically operable means for controllingoperation of the machine, a slide valve comprising a casing and a valvebody slidably mounted in said casing, said casing having a portcommunicating with a supply of air under pressure and portscommunieating with the plunger and the pneumatically operable means,said valve body having a passageway therein connecting the portcommunicating with the supply of air to the port communicating with theplunger at one position of the body and a second passageway connectingthe supply of air under pressure to the pneumatically operable device ata second position of the body, valve means connecting the pneumaticallyoperable device to said slide valve and means on said plunger forcontrolling operation of said last-mentioned valve means.

3. In a die casting machine which employs a gooseneck with a plungeroperating therein for discharging molten metal under pressure into a diecavity, the combination of a motor controlling operation of the machine,a switch controlling operation of the motor, pneumatic means foroperating said switch, means comprising a slide valve for controllingair operation of the plunger and said pneumatic means and means operableby said plunger for rendering said pneumatic means inoperable at oneposition of the plunger 4. In an automatically actuated die castingmachine employing a gooseneck with an air operated plunger therein fordischarging molten metal from the gooseneck into a die cavity and amotor controlling operation of the machine, the combination of an airactuated switch for controlling operation of the machine, a slide valveconnected to a supply of air under pressure, said valve connecting thesupply of air to the plunger at one position of the valve and to the airactuated switch at a second position of the valve, means connected tothe motor for moving said valve to said position, a check valvecommunieating with the air actuated switch and the supply of air underpressure and means on said plunger engaging with and holding said checkvalve closed at one position of the plunger.

5. In a die casting machine of the type employing a gooseneck with aplunger operating in the gooseneck for pressure discharge of moltenmetal in the formation of die castings and having an electric motor forcontrolling the operation of the machine, an apparatu for automaticallystopping machine operation upon fail ure of the plunger to complete anormal injection stroke, said apparatus comprising a switch in circuitwith said electric motor, an air actuated device for operating saidswitch, a valve connecting a supply of air under pressure to saidplunger at one position of the valve and to the air actuated device at asecond position of the valve, a check valve connecting the air actuateddevice to the supply of air under pressure through said first-mentionedvalve, said check valve hav- 6 ing an operating member and adjustablemeans on the plunger positioned for engagement with said operatingmember, said last-mentioned means engaging with and holding the checkvalve in closed position upon completion of a full stroke of theplunger.

LOUIS H. MORIN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,243,835 Brunner et a1. June-3, 1941 2,567,649 Morin Sept.11, 1951 FOREIGN PATENTS Y Number Country Date 568,873 Great BritainApr. 24, 1945

